南澎列岛恙虫病立克次体分离株的PCR/RFLP分析

目的　利用ＰＣＲ／ＲＦＬＰ方法证实南澎列岛是恙虫病的疫源地并对恙虫病立克次体初步分型。方法　采用套式聚合酶链反应（ＮＰＣＲ）扩增恙虫病立克次体５６ｋＤ蛋白基因片段，阳性标本的扩增产物进行限制性片段长度多态性（ＲＦＬＰ）分型。结果　南澎列岛的８ 株恙螨／野鼠分离株中７ 株与南澳岛的１ 株扩增出阳性带；ＲＦＬＰ图谱分析表明南澎列岛存在三个型别的立克次体感染，其中一型酶切图谱与Ｋａｒｐ 株相同，一型图谱与Ｋａｔｏ 相同，还有一型既不同于Ｋａｒｐ，也不同于Ｋａｔｏ、Ｇｉｌｌｉａｍ 。并且７株当中有５株为混合感染。南澳岛分离株酶切图谱与Ｋａｒｐ 株相同。结论　本文结果证实了南澎列岛和南澳岛是恙虫病疫源地。南澎列岛上存在三个型别的立克次体，不同型别的立克次体可形成双重感染

ANALYSIS OF ORIENTIA TSUTSUGAMUSHI ISOLATED IN NANPENG ISLANDS BY PCR AND RFLP

Aim\ To prove Nanpeng islands were endemic areas of scrub typhus and classify their genotypes by nested polymerase chain reaction(PCR),followed by restriction fragment length polymorphism(RFLP).Methods\ Nine strains of Orientia tsutsugamushi(O.t)isolated from wild rodents and mites in Nanpeng islands and Nanao island were examined by nested PCR-amplified 56KD type-specific antigen protein gene,and classified by RFLP.Results\ 8 of 9 strains tested positive,three genotype were found,which were Karp,Kato and a new type distinguishable from Karp,Kato and Gilliam;5 strains were cross-infection.Conclusion\ Those results suggested Nanpeng islands and Nanao island were endemic areas.Nanpeng islands existed three genotypic O.tsutsugamushi.Furthermore,cross-infection were observed in Nanpeng islands.